This got me looking at energy usage. I was surprised an electric car uses about 345 watts per mile. I though this low. If you drive 10,000 miles a year, that is 3,250,000 watts.
A 300 watt dissipating class A amp on 24 x 365 is 2,628,000
An HVAC is about 3500 watts per hour. In a warm state that is about 10 hours run time per day for say 182 days. Thats about 6,370,000 watts. That is assuming the home is about 2400 feet.
Heating a cooling is the mass power usage. Most homes I see in warmer states have more than 1 AC. They have 2 to 5. So the load is more like 12 to 18 million watts for summer. That does not include heat or cool in the winter.
At $1kW, that is $2,628 to idle an amp.
At $.12kW as is much of the US, that is $315. Thats $26 a month. Most audiophile have money enough to let their system run for $26 a month.
For perspective, your desktop computer uses at least 200 Watts per hour. I leave mine on 24 x 365. That is 1,752,000 watts. I bet your Taiko uses more than 200. I bet your DAC is also 200. We leave those on 24x365. Why pick on the amp when you digital front end is probably using close to twice what a class A amp uses. And about the same as what your home computer uses.
Rex we do tend to think in terms of energy use being just about the operational energy use… but if we’re trying to get a true picture of sum energy usage in a full life cycle assessment sense we should also be factoring in embodied energy, that is the energy used to create the product and to get it implemented before we ever start to use it.
With countries signing onto net zero greenhouse inventories user pays for true costs of the life cycle energy impacts of products or services becomes far more likely so we can expect costs for embodied energy will start to factor in the costs of component ownership.
Embodied or embedded energy varies by such a large degree for different materials and in the context of their sourcing and processing requirements. Usually embedded or embodied energy factors a large deal in the hidden true costs of the production of anything… we don’t really pay the true cost of production for anything and have just left it to future generations to cover those hidden costs… so carbon produced and environmental damage is offset into someone else’s future costs. Now we are starting to see the costs in terms of increasing costs of living from long term environmental costs.
So a passenger car (be it internal combustion or hybrid electric) has fairly huge embodied energy in creation phase. According to the translational ecology blog from the Nicholas School of Environment at Duke University says that David MacKay of the University of Cambridge estimates that the embodied energy in the average car amounts to about 76000 kWhr. That is equivalent to about five years of total electricity used in a 3200-square-foot house in Durham, NC. Also mentioned in this was in overall terms approximately a third of total energy usage on the planet is embedded in the production and the implementation phase of the energy usage cycle.
What factors play out in embodied energy. There is GER (gross energy requirements) or PER (process energy requirements). GER is truer and harder to calculate and the higher figure because it includes all PER but also all the other energy inputs beyond process. It’s not unusual to see GER to be twice as high as the PER.
In electronics cutting edge microprocessors are notoriously high in embedded energy requirements because they are so incredibly process intensive. Old school simpler tech like class a SET tube amps would tend to have far less energy intensive production requirements.
Apple’s LCA data on life cycle assessment and embodied energy for electronics published for their Mac computers and laptops used as some guide for the kinds of energy requirements for manufacture of contemporary IC intensive products such as solid state amplifiers and dacs that the PER process energy requirements for manufacture is often more than half of the sum energy of the total life energy use of the component and often outstrips operational energy. If we went then to a more true reflection using GER and factored that GER is considerably greater again it’s likely the figures for high tech contemporary electronics could well scale the total energy usage for manufacture and also operation of a solid state class d well past the life cycle energy requirements of a comparatively simpler tech class A tube amp.
A life cycle energy audit and proper carbon accounting would be a better reflection of the true circumstances on total energy use of any of this gear. Until we have that we’re just guessing about any true energy efficiency.